Grip portion for a writing instrument



FIG. 1 is a front elevational view of a grip portion for a writing instrument showing our new design;

FIG. 2 is a side elevational view, the opposite side being a mirror image thereof;

FIG. 3 is a rear elevational view; and

FIG. 4 is a perspective view thereof.

The environmental structure depicted by means of broken lines in FIGS. 1 through 4 is for illustrative purposes only and forms no part of the claimed design. 

The ornamental design for a grip portion for a writing instrument, as shown and described. 